/*背景雪花飘落特效*/
(function($){
    $.fn.snow=function(options){
        var $flake=$('<div id="flake" />').css({'position':'absolute','top':'-50px'}).html('&#10052;'),documentHeight=$(document).height(),documentWidth=$(document).width(),defaults={minSize:20,maxSize:40,newOn:300,flakeColor:"#f08080"},options=$.extend({},defaults,options);
        var interval=setInterval(function(){
            var startPositionLeft=Math.random()*documentWidth-100,startOpacity=0.5+Math.random(),sizeFlake=options.minSize+Math.random()*options.maxSize,endPositionTop=documentHeight-40,endPositionLeft=startPositionLeft-100+Math.random()*200,durationFall=documentHeight*10+Math.random()*5000;$flake.clone().appendTo('body').css({left:startPositionLeft,opacity:startOpacity,'font-size':sizeFlake,color:options.flakeColor}).animate({top:endPositionTop,left:endPositionLeft,opacity:0.2},durationFall,'linear',function(){
                $(this).remove()
            });
        },options.newOn);
    };
})(jQuery);
$.fn.snow({ minSize: 5, maxSize: 50, newOn: 700, flakeColor: '#FFF' });
